How do you know he had the authority to sell the house or who he is? 

Some valuable anecdotal and fact based evidence you've provided.Your email to the author really clears things up.

Only the entity that owns the property has any authority over the property, or any business communicating with tenants, unless it is the management co. 

I used to do it myself but now give them authority to do what makes sense for the company).

Maybe I just wasn't lucky but in an old place like this a small guy is the way to go when tenants are in the building and you just have to solve a damned problem.And as for dealing with tenant I'm just lucky she didn't call the housing authorities. 

Would the housing authority set the utility allowance after receiving paperwork from me?

I think its safe to suggest that many authorities from the DEA to local sheriffs are at odds at enforcing the changing laws as they balance the high costs to enforce it.Speaking of Trump...

The 'Silicon Valley' tag is the Forbes author's twist, but I think is clearly a bit of hyperbole designed to grab reader attention, something more and more difficult to do, especially for a piece of this length.

You would establish what I call a "Master Lease" where you essentially rent it from your parents and they give you the authority to "sublease" to a tenant.

To find the SEC 8 landlords, search for the Housing Authority website in your county, then find the tab or page for Housing Choice Voucher, then search for Available Housing.